Hi @Alok Aswal ,
Thanks for reaching out.
It seems attachment got missed in the post. I am assuming you have created a custom policy for Mobile OTP and Email OTP and defined separate technical profiles for both. You want to add a link to the custom UI that will open the Sign-in page for Email OTP screen and call the technical profile for Email OTP.
To achieve this, you can add a link to the custom UI that will redirect the user to the Sign-in page for Email OTP screen or you can add option button to select either Phone or mail OTP in the sign in page.
You can follow https://github.com/azure-ad-b2c/samples/tree/master/policies/mfa-email-or-phone to set up similar scenario in your application.
Hope this will help.
Thanks,
Shweta
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